Microdecompression versus Open Laminectomy and Posterior Stabilization for Multilevel Lumbar Spine Stenosis: A Randomized Controlled Trial

Table 6

The mean differences of operation time and amount of blood lost between study groups.

Study variables	Study groups	N	Mean	SD	t-test	value
Operation time (minutes)	Group A	50	118.10	9.30	−38.78	<0.001
	Group B	50	178.00	5.71
Blood lost (ml)	Group A	50	77.50	9.54	−64.03	<0.001
	Group B	50	308.20	23.62